Abstract:
Thermal comfort is that state of mind of an individual that is satisfied with the thermal environment. In this research work, the magnitude and spatio-temporal variation of outdoor bioclimatic conditions of five southwest-Nigeria states were examined. The meteorological data used for this research work includes observed mean monthly values of air temperature (°C), relative humidity (%), windspeed (m/s), vapor pressure (hpa) and cloud cover (octas) for the period (1983 – 2012) obtained from the Nigerian Meteorological Agency (NIMET) Oshodi-Nigeria. Previous comfort analyses of Nigeria climate showed that thermal bioclimate of Nigeria require more than a single index for adequate research. Temperature Humidity Index (THI) and Physiologically Equivalent Temperature (PET) were used. Air temperature was observed to be the highest contributing meteorological parameter to thermal conditions. Trend pattern show that discomfort level deteriorated over the years, most noticeable is the last decade of the study period. The years 1987 and 1998 were marked period of peak discomfort in the entire region. The result also show three different grades of thermal discomfort conditions namely; slightly warm, warm and hot over the tropical wet, and tropical wet and dry zones. In conclusion, thermal discomfort was observed to decrease from the northern part of the region towards the southern part of the region in the period examined.
